<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <input type="number" name="number" id="">
    <script>
        // let hd = "houduren";
        // console.log(Number(hd));
        // console.log(NaN == NaN);

        // console.log(Number.isNaN(2 / "jifeji"));
        // console.log(Object.is(2 / "jifeji", NaN))

        // 类型转换
        // console.log(Number(false));
        // console.log(Number(true));
        // let hd = 89;

        // console.log(Number(hd));
        const number = document.querySelector("[name='number']").value;
        console.log(typeof number);
    </script>
</body>

</html>